Libjpeg used in NetSurf for decoding of JPEG images handles exceptions using a
pair of non-local jump functions: setjmp() and longjmp(). When a decompression
context is created via a call to the function jpeg_create_decompress() the
caller passes a structure jpeg_decompress_struct as a parameter. This structure
should has a validly initialized jump buffer, so the initialization or other
functions called in future can jump to the exception handling context.
The jpeg backend of NetSurf now initializes libjpeg mistakenly: jump buffer is
filled after the call to jpeg_create_decompress(). It results in jump to random
addresses in the case of exception caught during operation of the function
jpeg_create_decompress().
The patch moves the initialization of jump buffer before the call to
jpeg_create_decompress().
Signed-off-by: Sergei Rogachev <rogachevsergei@gmail.com>
bitmap file decoding is done at first call to redraw but was not
calling the modified callback at the correct time immediately after
decode so frontend image chnages were not being done. This caused
nsgtk to fail to apply its colour space fixups so red was swapped with
blue.
